- A pendulum which is suspended from the ceiling of a railroad car is observed to hang at an angle of 10 degrees to the right of vertical. Which of the following answers could explain this phenomena?
A. The railroad car is at rest.
B. The railroad car is accelerating to the left.
C. The railroad car is moving with constant velocity to the right.
D. The railroad car is accelerating to the right.
2. Two forces have magnitudes of 11 newtons and 5 newtons. The magnitude of their sum could NOT be equal to which of the following values?
A. 16 newtons
B. 5 newtons
C. 9 newtons
D.7 newtons
- A ball leaves a girl’s hand with an upward velocity of 6 meters per second. What is the maximum height of the ball above the girl’s hand?
4. A boy throws a ball vertically upward with a velocity of 6 meters per second. How long does it take the ball to return to the boy’s hand?
5. A toy train moves in a circle of 8 meters radius with a speed of 4 meters per second. What is the magnitude of the acceleration of the train?